Have any advances been made in figuring out just how to remove
libsystemd0 from a Debian 9 machine that's running sysvinit? The
ongoing presence of libsystemd0 has caused slowly-progressing trouble
with several machines of mine culminating in complete failure a couple
days ago. Initially I thought this was unrelated to systemd, but now I
tracked it down to systemd's remnants and the problem is progressing
much faster with freshly-installed machines.

First, how exactly did you convert to sysvinit, etc? And what kind of
trouble?
I've been running Stretch with sysvinit for almost a year -- as
a personal machine, not a server -- and have had absolutely NO
problems. Here's the link I used:
http://without-systemd.org/wiki/index.php/How_to_remove_systemd_from_a_Debian_Stretch_installation
I used the very first conversion steps, the simplest one, and none
of the optional ones. No pinning. No third-party systemdless repos,
etc. I still have systemd libraries including libsystemd0 for those apps
that have systemd as a dependenciy. No problems. Totally removing
systemd is a pain requiring third-party systemdless repos and keeping a
wary eye out for problems. I did it a couple times as part of my
experiments, and always had glitches.
One thing did just occur to me: Are you using the GNOME desktop? I've
heard stories about it and systemd. It is VERY dependent on it. I
haven't used GNOME whatever version for about 7 years. I use only a
window manager Openbox.

I followed that same thing you did as soon as the machine was installed.
I also did optional steps 2 and 3. I didn't do 1 because all the machines
in question are headless. I stopped using GNOME when version 3 came out
and switched to MATE for most of my desktop needs.

One of the symptoms that made me think libsystemd0 had something to do
with it was the output of "apt-get upgrade". It would always report "1
not upgraded" or "2 not upgraded".

The trouble manifested in dependency hell and networking that would
mysteriously stop for no readily apparent reason (on reboot after kernel
upgrade or out of the blue). Usually networking could be regained by
doing a LISH login and manually turning on the network interfaces. Then
interface names started changing randomly. This was after names like
"eth0" and friends were abandoned. Servers died by way of networking only
working halfway, no matter what I did. I was able to ssh in and do scp
and rsync transfers, but that was about it.

What's the point of allowing libsystemd0 to exist when systemd has been
purged?

Is anyone working on a mechanism to allow for install-time selection of a
desired init? I brought this up a few times since systemd came to Debian,
but I've never heard anything more on this.

--
David Griffith
dave@xxxxxxx
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